4 Answers
4

There have been stories for years of mail order (and now online) retailers that pull a scam that goes something like this:

You respond to an ad for an insanely low price on a lens. They accept your order and bill your credit card.

A few days later they contact you to say the exact lens is out of stock, but they will sell you the upgraded version for only $$ more.

If you tell them you will wait on the item you originally ordered they will never send you anything (mainly because that version does not exist at all). They will try to string you along until it is too late to reverse the charge on your credit card.

If you agree to the upgrade, you wind up paying more than you would have if you had bought the lens from a reputable dealer to begin with.

To the best of my knowledge, Canon has never made the same lens with both plastic and steel mounts. They have never released an "L" lens with a plastic mount. The only Canon lenses I've ever seen with plastic mounts were kit lenses, including the EF 50mm f/1.8 that was once available as a kit lens with early EOS film bodies. The EF-S 18-55mm f/3.5-5.6 has a plastic mount, as did the old EF 28-80mm and 28-90mm lenses that came with a lot of film Rebels.

Never heard of that. While disproving it 100% is impossible, I would be extremely doubtful if Canon make lesser L-lenses.

Most likely you are dealing with a shady vendor and you should avoid them. The difference between local and imported versions is usually in the scope of the warranty and documentation language.

Know that an import version is local somewhere else and a local version is an import elsewhere, so there would be very little reason to produce lesser-quality versions. When it comes to cameras rather than lenses, you may have a different charger or power-cord.

Nikon made two versions of the old 70-300. One had a plastic mount, the other metal. However these were not produced at the same time - one version replaced the other at some point. I have never, ever heard of a manufacturer offering a metal mount as an upgradeable option. Definitely smells like scam.

The "import" you are referring to is also termed "Grey Market". The products marked as "USA" and "Import" are most often identical. In the case of Canon "L" series lenses both will be "Made in Japan" If not then there is a problem:

"On the back of Canon lenses is a six-digit code, which indicates
where the lens was manufactured and when.Example of a code "UV1212"
The first letter 'U' represents the factory that made the lens. Three
possible first letters are: U = Utsunomiya, F = Fukushima, O = Ōita" source: Wikipedia

You can find more detailed information about B&H Grey Market Items here.